长期应激对成年大鼠操作性条件反射及性激素水平和脂质过氧化作用的影响

本文观察了长期电击刺激,长期低剂量γ射线照射以及两者相加的应激刺激对成年雄性大鼠机体功能的影响,结果表明:上述应激刺激均明显抑制成年大鼠生长,促进大鼠操作性条件反射的形成,仅电击条件下条件反射的消退延缓。三种刺激对血浆睾酮及睾酮与雌二醇比值无明显影响,但刺激8周后E_2水平有所升高,长期照射条件下血浆MDA升高。长期电击与电击加照射16周后大鼠胸腺萎缩明显加速。长期低剂量γ射线照射后全血白细胞计数明显下降,其中淋巴细胞比例减少,粒细胞比例升高。以上结果表明上述三种长期应激刺激对成年大鼠生长,操作性条件行为和性激素、脂质过氧化作用均有一定影响,而且不同的应激刺激具有不同的作用特点。

Effects of Long-term Stress on Operant Conditioning Behavior, Sex Hormone and Lipid Peroxidation in Adult Rats

Male adult Wistar rats were submitted to the following long-term stress stimulations for 8 or 16 weeks. (1) electric shock, (2) low dose gamma-ray irradiation, (3) electric shock plus irradiation. The growth of the rats was significantly inhibited under these conditions. No significant difference of operant conditioned reflex of the rats was observed in the experiment. Plasma estradiol level in male rats increased significantly after 8 weeks of electric shock, irradiation, or combined treatments. Long-term low dose gamma-ray irradiation also increased plasma MDA accumulation in rats. The thymus atrophy was accelerated by long-term electric shock and electric shock plus irradiation. There was no difference of adrenal weight between the control and the stressed groups. Further investigations on the cellular immune function, and lipid peroxidation in various tissues of the body are in progress.